Appliance with multiple lid control switches



Jan. 3, 1967 T. GIUSEPPE APPLIANCE WITH MULTIPLE LID CONTROL SWITCHES Filed Nov. 10, 1964 ATTORNEY United States Patent Ofiice 3,295,649 Patented Jan. 3, 1967 3,295,649 APPLIANCE WITH MULTIPLE LID CONTROL SWITCHES Tanzi. Giuseppe, 21 Via Orocco, Comerio, Italy Filed Nov. 10, 1964, Ser. No. 410,083 7 Claims. (Cl. 192-136) This model of utility relates to a household electric appliance and in particular to a washing machine or to a centrifugal hydroextractor, wherein special means are provided to stop the rotating masses that are usually accessible to the operator, thereby excluding any danger that might arise, due to his hands coming into contact therewith.

As already well known, the drum of washing machines, and the basket of centrifugal hydroextractors are driven at high speeds, up to 600 rpm. Thus, it is essential to prevent any possibility that the operator may come into contact with said components, when driven at such high speeds, if accidents are to be avoided. Thus, such machines are equipped with a switch, that is interlocked with the door through which said drum or basket can be acceded to, and by which the motor is switched off when same door is being opened. Moreover, since such precaution would be in, and by itself insufficient due to remarkable inertia of masses, a braking system, embodied in such machines, enters into action when said door is being opened.

The above precaution is-obviously expensive, owing to required braking equipment, and the main purpose of this invention consists in the provision of another braking system, which is simpler and more economical, while giving satisfactory results.

According to the innovation, the above results ar obtained in a household electric appliance which is characterized in that it comprises, in combination, rotating components to which the operator can accede, a change-pole electric motor by which same rotating components are driven at two difierent speeds, two series-connected doors by which the access to said components is prevented, a diverter switch operated by the first of said doors, and a circuit breaker operated by the other of said doors, the whole in an arrangement such that, when the first door is opened, the motor is operated at its lower speed, while when the second door is opened, the motor is switched-01f by the related circuit breaker.

In other words, when the first door is opened, the diverter is switched-over to the position wherein all poles of the motor are connected, while when the second door is opened, the switch through which same motor is fed, is also opened.

Thus, the arrangement according to the invention allows to obtain in a first step the switching of an appliance motor over to a lower rpm, and in the second step a power cutout, and thus a spontaneous and quick stopping of all rotating components of the appliance.

It has been ascertained that the time interval between the two consecutive operations of door openingeven if very shortis always sufficient to otbain the required slowing down of rotating components by means of the electric braking thereby preventing that the operator may accede to the same components, when they are driven at a higher r.p.m., being thereby dangerous.

The time elapsing between the opening of second door, and the complete stopping of rotating components is so short that by performing the manipulation at a normal rate, the access to same components is allowed only when they have nearly stopped. Even if the opening of the sec ond door is intentionally accelerated by the operator, he may :reach the rotating components when they are yet moving; however, the motion thereof will have been already slowed down to such an extent that a danger is no more incurred in touching them.

The invention will be better appreciated from the following detailed description, taken with the accompanying drawings, both description and drawing given as a nonrestrictive example only. In same drawing:

FIG. 1 diagrammatically shows the household electric appliance as realized according to teachings of this invention, and

FIG. 2 shows the portion of circuitry of same household appliance, as required for a good understanding of the invention.

Referring now to same figures, 1 is the household electric appliance in its whole (in the considered example, a washing machine). Such appliance is comprisive of a rotating drum or basket 2, wherein the linen or clothing is loaded, and to which the operator can accede through the doors 3 and 4, that are series connected with one another. The door 3 is located on the upper face of machine casing, and can be swung in the direction of arrow A on the hinge axis 5. The second door 4 is fitted concentric with the drum or basket 2, and can be run on its guides 6, in the direction of arrow B, in order to accede to inside of basket. A motor, diagrammatically indicated as 7, cmbodied in the appliance, is designed to drive the basket 2 through a reduction gear, diagrammatically indicated as 8. The electric motor 7 is of the change-pole type, i.e., the number of their poles can be changed, to have it operated at different speeds, e.g., two speeds, or a lower r.p.m. for the washing, and a higher rpm. for the centrifugation of linen.

According to the invention, the door 3 is designed to co-operate with a diverter switch 9. In more detail, when said door is closed, the movable contact of said switch 9 is in the position as shown with a continuous line in the FIG. 2, whilst when same door is open, said movable contact 9a is in the position as shown with dash lines in same figure.

A switch 10 is interlockedwith the door 4. Such switch is closed when said door 4 is also closed, i.e., when the basket 2 is not accessible by the part of the operator, and is open after same door has been opened.

In the FIG. 2, C and D are the leads of single phase net, to which the feeding and control c 'ircuit of motor 7 are connected; such circuit is comprisive of the usual sequence controlled contacts, for the switching from one speed, over to another speed, and that are fitted in the section X; and of the main switch 11.

According to the invention, the circuitry is also comprisive of the diverter switch 9 and of switch 10.

When the machine is in operation, and both doors are closed, the contact 9a is in the position shown by a solid line, and the switches 10 and 11 are closed. Let us also assume that the machine is operating at the centrifugal hydroextractor speed. Under such conditions, the motor is fed through the lead 12, and is running at the highest rpm. When the door 3 is opened, the contact 9a is brought into the position as shown with dash lines, whereby the motor is now fed through the lead 13, and will run at its lowest speed. Finally, by opening the door 4, the switch 10 is also opened, thereby switching off the motor, which is thereby quickly stopped.

What I claim is:

1. An appliance with means for variable speed control comprising, in combination, a housing for said appliance; operating means within said housing and operable at variable speeds; variable speed motor means connected to said operating means for actuating same; a power source connectable to said motor means for driving same; a first door associated with said housing and providing Vaccess to the interior thereof; means associated with said first door and reducing the speed of said motor means in response to the opening of said first door; a second door accessible from said first door and having means associated therewith for further reducing the speed of said motor means in response to the opening of said second door.

2. An appliance according to claim 1 wherein said variable motor means is a change-pole motor capable of operating at two different speeds.

3. An appliance according to claim 1 wherein said means associated with said first door for reducing the speed of said motor means is a switch operatively connected to said first door, said switch connecting said power source to said motor means so as to drive the latter at reduced speed.

4. An appliance according to claim 1 wherein said means associated with said second door for further reducing the speed of said motor means is a switch connecting said power source to said motor means when said second door is closed and disconnecting said power source from said motor means when said second door is opened.

5. An appliance according to claim 1 wherein said power source is an electrical source.

6. An appliance according to claim 1 wherein said first door is disposed at the surface of said housing and provides access to the interior thereof and to said second door.

7. An appliance according to claim 1 wherein said second door is situated within the interior of said housing and provides access to said operating means.

References Cited by the Examiner UNITED STATES PATENTS 4/1933 Schaum 192l36 X 9/1965 McMillan 192136 X 

1. AN APPLIANCE WITH MEANS FOR VARIABLE SPEED CONTROL COMPRISING, IN COMBINATION, A HOUSING FOR SAID APPLIANCE; OPERATING MEANS WITHIN SAID HOUSING AND OPERABLE AT VARIABLE SPEEDS; VARIABLE SPEED MOTOR MEANS CONNECTED TO SAID OPERATING MEANS FOR ACTUATING SAME; A POWER SOURCE CONNECTABLE TO SAID MOTOR MEANS FOR DRIVING SAME; A FIRST DOOR ASSOCIATED WITH SAID HOUSING AND PROVIDING ACCESS TO THE INTERIOR THEREOF; MEANS ASSOCIATED WITH SAID FIRST 